Evaporator
After boiling, was provisionally decided evaporator can be selected from the data directory or intended for these purposes. Rating of the evaporator will be proportional to the temperature difference between the refrigerant and cooling medium. Since the last changes in temperature as it passes through the surface of the cooler, the exact calculation for a particular load is tedious and prone to errors.
To simplify the selection of air cooling evaporators for condensing units, evaporator responsibilities, usually expressed in the major ratings (see Fig. 10.1), in terms of kilowatt in degrees Kelvin. This rating factor is multiplied between the incoming air and refrigerant.
This factor, the main thing-rating, it is assumed unchanged and design working range cooler, and this approach is good enough for the selection of equipment. The main rating will change the mass flow rate and, to a lesser extent, with a working temperature. This can vary significantly with liquids, such as glycol brines, as viscosity and, consequently, the coefficient of convective heat transfer alter at lower temperatures. In unusual applications, the provider should consult.....
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Component selection and balancing 